NBFC under RBI & CLB

I would Like to Know how NBFC are controlled By RBI & CLB. As My experience show they are under no compulsions or regulation regarding commitments to customers. I have a case where the customer has cleared all dues of the NBFC. for which NBFC has issued written statement, But still the NBFC is not giving an NOC to its customer. Firstly there is no information available on website of the NBFC, the superior officer passes on responsibilty to customers service agent, the customers service agent does not answer call or meet the client. Flatly NBFC is refusing to give NOC openly saying you can complain to whomso ever you like . I would like to request help from this forum for taking right steps to take it up with the rigth authority at RBI & CLB.